Description

Yesterday we realized that we should actually not drop usage tracking for deleted entities: we need the tracking entries so we know which pages to re-render when the entity is restored. This is analogous to the fact that we store red links in pagelinks.

Maybe they should get a different usage or modified usage so that these 'usages' can be filtered out when generating stats and so that people can find them.

We decided quite a while ago that we would track entity usage regardless of whether the entity actually exists, just like the link table tracks links regardless of whether the page exists. So we don't need to do anything upon deletion.